Please advise on how to feed a child. The child chooses food. I want t…

Please advise on how to feed a child. The child chooses food. I want to feed them properly. They might eat 1-2 tablespoons, then shove their food in my face or throw it up. They refuse porridge, but my mom says they eat porridge. I'm afraid that breast milk is not enough for full growth. We eat fruits and fruit purees with appetite.